/Engine/Plugins/FX/Niagara/Source/Niagara/Classes/NiagaraDataInterface.h
Allows data interfaces to influence the compilation of GPU shaders and is only called on the CDO object not the instance.
virtual void ModifyCompilationEnvironment ( EShaderPlatform ShaderPlatform, struct [FShaderCompilerEnvironment](API\Runtime\RenderCore\FShaderCompilerEnvironment) & OutEnvironment ) const